1. Field of the Invention
The invention relates generally to electronic circuits, and more particularly to systems and methods for laying out wiring between a first set of circuit components and a second component.
2. Related Art
With advancements in electronics technology, there is constantly a demand for improved electronic devices. Aside from the demand for new features in these devices, there is a demand to make the same devices smaller and faster. In order to make electronic devices smaller and faster, it is normally necessary to make the components that form the devices physically smaller. Decreasing the size of these components, however, can result in problems that prevent the devices from operating more quickly, and may even cause the devices to malfunction.
As the size of electronic components decreases, the size and spacing (pitch) of the wires connecting these components also decreases. As the pitch of the wires in an electrical circuit decreases, the coupling capacitance of these wires increases. The increased coupling capacitance in turn results in increased interference between the wires. Additionally, as the complexity of the electronic circuits increases, longer wires (and more widely varying lengths of wires) may be necessary to connect individual components within the circuit. The increased length of the wires results in increased resistance on these wires.
The increased capacitance and resistance of wires in electrical circuits may lead to some signal paths being effectively longer than others. In other words, it may take longer for a signal to traverse a path over a wire with higher resistance and capacitance than a path over a wire with lower resistance and capacitance. This is problematic in circuits which couple signals from a large number of components into another component because it is difficult to keep the signal paths the same length. As a result, it may take different amounts of time for the signals to reach the end component, and the phases of the signals may consequently become skewed with respect to each other. Further, because the capacitance is greatest in the longest signal lines, the increased time necessary to traverse the longest signal lines forces the circuits to be operated at slower speeds.
Conventionally, the problems caused by the capacitance between the signal lines is addressed in either of two ways. First, the width of the wires may be increased in order to reduce their resistance. By reducing the resistance of the wires, the signal paths are effectively shortened and less skew results from the signals traversing the different signal paths. The second way the problem is addressed is by increasing the pitch of the wires. In other words, the spacing of the wires is increased. By increasing the pitch of the wires, the coupling capacitance between the wires is decreased. The decreased capacitance result in reduced interference and less skew between the signals.
The problem with these conventional solutions to the problem is that, by increasing the width of the wires or by increasing the spacing between the wires, the size of the circuit is increased. This goes against the desired reductions in size. It would therefore be desirable to provide systems and methods for reducing the skew between signal lines without increasing the size of the circuit in which the signal lines are used.